Sluggish sales made plug-in cars a favorite target of conservative commentators, a symbol of Big Government foisting pricey green technologies on an unwilling public. Critics rebranded the Chevy Volt as the "Obama car" and used its low sales figures to bash the federal bailout of General Motors.

But even as plug-in cars came under attack, their sales slowly grew. The numbers are still small, making up a tiny slice of the automotive market. But they rose steadily in 2012 as automakers introduced more models of electric cars and advanced hybrids.

"It's definitely a strong showing by both all-electrics and plug-in hybrids this year," said Jeremy Acevedo, supervisor of industry analysis with the Edmunds.com auto information website. "We're seeing more cars for more people."

In 2011, Americans bought 9,754 electric cars and 7,671 plug-in hybrids, according to Edmunds. This year, sales of electrics reached 10,407 by the end of November, while plug-in hybrids hit 31,042.

And those figures don't count the new Tesla Motors Model S, which hit the market in June. Palo Alto's Tesla, which reports sales figures only once each quarter, has taken 13,000 reservations for the all-electric Model S and expects to deliver 2,500 to 3,000 by the end of the year.

The much-derided Volt, meanwhile, has emerged as the field's leader.

GM sold 7,671 Volts in 2011, the first full year of sales. This year, drivers bought 20,828 Volts through the end of November. At that pace, the car's sales total for the year could hit 22,000.

Volt gaining

Consumers seem to be warming to the Volt's technology. The car runs on electricity alone for the first 25 to 50 miles of a trip, then switches to gasoline - lessening the fear of running out of electric power, something that has dogged sales of pure electrics, such as the Nissan Leaf.

"With a Leaf's limited range, you really have to make that lifestyle choice. But with a plug-in hybrid, you get to experience an electric car without range anxiety," Acevedo said. "It's a really convenient, easy step."

The Leaf, the first all-electric car for the mass market, hasn't gained the same traction as the Volt, at least not in America. Sales through the end of November totaled 8,330, putting Nissan on pace to sell slightly more this year than the 9,674 it sold in 2011. Brendan Jones, director of electric vehicle marketing for Nissan North America, said the company has sold nearly 50,000 Leafs worldwide since the car hit the market.

"This does take time," he said. "We're happy with the trajectory we're on right now. We'd like to do anything we can to accelerate it."

Plug-in cars still face stiff headwinds. A recent survey by Pike Research found that only 35 percent of consumers were very interested in buying an electric car or advanced hybrid, down from 44 percent in 2010. Many of the people who responded didn't understand the technology, with 37 percent, for example, saying the cars' batteries were dangerous.

Prices remain high: $35,200 for a base-model Leaf and $39,145 for a Volt. And plug-ins must compete against a new generation of cheap, fuel-sipping cars that run on gasoline.

"There are more and more vehicles out there that get 40 miles per gallon, and people are very comfortable with that," said John Viera, global director of sustainability for Ford Motor Co. This year, Ford introduced an electric version of the Focus as well as a new hybrid, the C-Max.

The current wave of plug-in vehicles is still young, with sales starting in late 2010. So far, buyers have been limited to a clutch of early adopters who are interested in new technology, concerned about the environment and determined to break society's addiction to oil. A few even drove cars from the last wave of electric vehicles in the 1990s, cars that never reached mass production.

"The early adopters, you could send them a kit of parts and they'd build their own vehicle," Viera said.

Bill Gravitt of San Francisco has an old Jet Electrica, a compact plug-in from the 1980s. This year, he added a Mitsubishi i-MiEV, a no-frills electric car with a range of roughly 70 miles per charge. Small and shaped like an egg, it handles well, accelerates quickly and serves as his day-to-day car, while he keeps a Ford Explorer at home for longer trips.

Fighting Big Oil

Gravitt likes the lower cost of using only electric power. But he also sees the car as a way to fight Big Oil.

"I want to do the right thing," said Gravitt, a self-employed property manager. "I resent the hold the oil companies have over the United States. I do everything I can to boycott oil."

Mindful that they need to reach a broader audience, a few automakers have focused on making high-performance plug-ins, designed to appeal to people who love driving. That's true of Tesla, whose CEO, Elon Musk, brags that the Model S is the best car of any kind, not just among electrics. The car is priced accordingly, ranging from $57,400 to $105,400 before state and federal incentives are factored in.

San Francisco attorney Richard Zitrin bought a Model S this year. And while he, like Gravitt, wants to wean society off fossil fuels, Zitrin loves the Model S first and foremost as a car.

"It is far and away the best car I've ever driven - not even close," he said. "The acceleration from a stop is extraordinary, because there's no revving up. The handling, even at speed, is extraordinary."

So far, Tesla's only Model S sales update covered the period from the car's launch in late June through the end of September. During that time the company delivered more than 250 cars. Tesla executives, however, say that the pace of production at the company's factory in Fremont has increased substantially since then, and deliveries should rise as well.